Bonding Apparatus and Method

ABSTRACT

The present disclosure relates to methods and apparatuses for mechanically bonding substrates together. The apparatuses may include a pattern roll having three or more pattern elements protruding radially outward, wherein each pattern element includes a pattern surface. The pattern surfaces are also separated from each other by gaps having minimum widths. The pattern roll may be adjacent an anvil roll to define a nip between the pattern surfaces and the anvil roll, wherein the pattern roll is biased toward the anvil roll to define a nip pressure between pattern surfaces and the anvil roll. As substrates advance between the pattern roll and anvil roll, the substrates are compressed between the anvil roll and the pattern surfaces to form a discrete bond region between the substrates. During the bonding process, some of yielded substrate material also flows from under the pattern surfaces and into the gaps to form gap grommet regions.

FIELD OF THE INVENTION

The present disclosure relates to methods for manufacturing absorbentarticles, and more particularly, to apparatuses and methods for bondingsubstrates that may be used as components of absorbent articles.

BACKGROUND OF THE INVENTION

Along an assembly line, various types of articles, such as for example,diapers and other absorbent articles, may be assembled by addingcomponents to and/or otherwise modifying an advancing, continuous web ofmaterial. For example, in some processes, advancing webs of material arecombined with other advancing webs of material. In other examples,individual components created from advancing webs of material arecombined with advancing webs of material, which in turn, are thencombined with other advancing webs of material. In some cases,individual components created from advancing web or webs are combinedwith other individual components created from other advancing web orwebs. Webs of material and component parts used to manufacture diapersmay include: backsheets, topsheets, leg cuffs, waist bands, absorbentcore components, front and/or back ears, fastening components, andvarious types of elastic webs and components such as leg elastics,barrier leg cuff elastics, stretch side panels, and waist elastics. Oncethe desired component parts are assembled, the advancing web(s) andcomponent parts are subjected to a final knife cut to separate theweb(s) into discrete diapers or other absorbent articles.

During the assembly process, various components and/or advancing webs ofmaterial may be bonded together in various ways. For example, in someprocesses, advancing webs and/or components may be bonded together withadhesives. In other processes, advancing webs and/or components may bemechanically bonded together with heat and pressure without the use ofadhesives. An example of such a mechanical bonding method and apparatusis disclosed in U.S. Pat. No. 4,854,984, wherein two laminae are bondedtogether by advancing through a nip between a patterned cylinder and ananvil cylinder. Pattern elements on the patterned cylinder exertpressure on the two laminae against the anvil roll to create discretebond sites. More particularly, bond sites are created as the extreme nippressure compresses and yields the laminae material in areas between thepattern elements and the anvil. During the bonding process, some of theyielded material may flow from the bond site to areas surrounding theperimeter of the pattern element.

However, extreme nip pressures may exceed the compressive yield strengthof cold work powder metal tool steels. In addition, current mechanicalbonding methods are susceptible to pattern element chipping, spalling,buckling, and/or otherwise fracturing, referred to generally as bondtool breakdown, sometimes necessitating frequent and costly repairs.These mechanical bonding methods may also damage the laminae by formingholes and/or tears in or around the bond sites. For example, patternelements may become deformed and/or fail after prolonged use due to highstresses that occur in the center portions of the pattern element duringthe bonding operation. In some instances, such high stresses may causecraters to form in the bonding surfaces of pattern elements. As apattern element degrades, the bonds created thereby may haveinconsistent aesthetic appearances; have relatively weaker strengths;and may tear or cut the bonded laminae in areas adjacent to the bonds.In addition, as the web basis weight of laminae decreases, bonds maybecome more susceptible to bond defects such as tearing and pinholes atrelatively high nip pressures.

Consequently, it would be beneficial to provide a method and apparatusfor mechanically bonding substrates that produces bond sites withrelatively low damage to the laminae and with reduced bond toolbreakdown.

SUMMARY OF THE INVENTION

The present disclosure relates to methods and apparatuses formechanically bonding substrates together. The apparatuses may include apattern roll having three or more pattern elements protruding radiallyoutward, wherein each pattern element includes a pattern surface. Thepattern surfaces are also separated from each other by gaps havingminimum widths. The pattern roll may be adjacent an anvil roll to definea nip between the pattern surfaces and the anvil roll, wherein thepattern roll is biased toward the anvil roll to define a nip pressurebetween pattern surfaces and the anvil roll. As substrates advancebetween the pattern roll and anvil roll, the substrates are compressedbetween the anvil roll and the pattern surfaces to form a discrete bondregion between the substrates. During the bonding process, some ofyielded substrate material also flows from under the pattern surfacesand into the gaps to form gap grommet regions.

In one embodiment, an apparatus for dynamically bonding substratescomprises: an anvil roll; a bonding roll including: base circumferentialsurface; a first pattern element including a first pattern surfacehaving a first pattern area, A1, wherein A1 is greater than about 0.25mm² and less than about 2.00 mm², wherein the first pattern elementprotrudes outward from the base circumferential surface to define adistance, Hp1, between the first pattern surface and the basecircumferential surface, and wherein the first pattern element isbounded by a first perimeter; a second pattern element including asecond pattern surface having a second pattern area, A2, wherein A2 isgreater than about 0.25 mm² and less than about 2.00 mm², wherein thesecond pattern element protrudes outward from the base circumferentialsurface to define a distance, Hp2, between the second pattern surfaceand the base circumferential surface, and wherein the second patternelement is bounded by a second perimeter; and a third pattern elementincluding a third pattern surface having a third pattern area, A3,wherein A3 is greater than about 0.25 mm² and less than about 2.00 mm²,wherein the third pattern element protrudes outward from the basecircumferential surface to define a distance, Hp3, between the thirdpattern surface and the base circumferential surface, and wherein thethird pattern element is bounded by a third perimeter; wherein the firstand second pattern surfaces are separated by a first gap having aminimum width, D1, wherein the first and third pattern surfaces areseparated by a second gap having a minimum width, D2, and wherein thesecond and third pattern surfaces are separated by a third gap having aminimum width, D3, and wherein D1, D2, and D3 are greater than 0.20 mmand less than about 3.00 mm; and wherein the bonding roll is adjacentthe anvil roll to define a nip between the first, second, and thirdpattern surfaces and the anvil roll; and wherein the bonding roll isbiased toward the anvil roll to define a nip pressure of greater thanabout 40,000 PSI and less than about 60,000 PSI between each patternsurface and the anvil roll.

In another embodiment, a method of bonding substrates comprises thesteps of: rotating an anvil roll; rotating a pattern roll adjacent theanvil roll, the pattern roll including a base circumferential surface, afirst pattern element including a first pattern surface, a secondpattern element including a second pattern surface, and a third patternelement including a third pattern surface; wherein each pattern surfacedefines an area, A, wherein A is greater than about 0.25 mm² and lessthan about 2.00 mm²; wherein each pattern element protrudes outward fromthe base circumferential surface to define a distance, Hp, between thefirst, second, and third pattern surfaces and the base surface, andwherein each pattern element is bounded by a perimeter; wherein thefirst and second pattern surfaces are separated by a first gap having aminimum width, D1, wherein the first and third pattern surfaces areseparated by a second gap having a minimum width, D2, and wherein thesecond and third pattern surfaces are separated by a third gap having aminimum width, D3, and wherein D1, D2, and D3 are greater than 0.20 mmand less than about 3.00 mm; biasing the bonding roll toward the anvilroll to define a nip pressure of greater than about 40,000 PSI and lessthan about 60,000 PSI between each pattern surface and the anvil roll;advancing a first substrate and a second substrate in a machinedirection between the pattern roll and the anvil roll; and compressingthe first substrate and the second substrate between the anvil roll andthe first, second, and third pattern surfaces to form a discrete bondregion between the first and second substrates.

In yet another embodiment, a laminate comprises: a first substratecomprising nonwoven fibers; a second substrate comprising nonwovenfibers; a discrete bond between the first substrate and the secondsubstrate, the discrete bond comprising: a first membrane regioncomprising nonwoven fibers of the first and second substrates that havebeen yielded under pressure and are fused together, defining a firstarea, A1, greater than about 0.25 mm² and less than about 2.00 mm²; asecond membrane region comprising nonwoven fibers of the first andsecond substrates that have been yielded under pressure and are fusedtogether, defining a second area, A2, greater than about 0.25 mm² andless than about 2.00 mm²; a third membrane region comprising nonwovenfibers of the first and second substrates that have been yielded underpressure and are fused together, defining a third area, A3, greater thanabout 0.25 mm² and less than about 2.00 mm²; a first gap grommet regionseparating the first membrane region and the second membrane region,wherein the first gap grommet region comprises material of the first andsecond substrates that has been transferred from the first membraneregion and second membrane region, and wherein the first gap grommetregion defines a minimum width, D1, that is greater than 0.20 mm andless than about 3.00 mm; a second gap grommet region separating thefirst membrane region and the third membrane region, wherein the secondgap grommet region comprises material of the first and second substratesthat has been transferred from the first membrane region and thirdmembrane region, wherein the second gap grommet region defines a minimumwidth, D2, that is greater than 0.20 mm and less than about 3.00 mm; athird gap grommet region separating the second membrane region and thirdmembrane region, wherein the third gap grommet region comprises materialof the first and second substrates that has been transferred from thesecond membrane region and the third membrane region, wherein the thirdgap grommet region defines a minimum width, D3, that is greater than0.20 mm and less than about 3.00 mm; an outer grommet region partiallysurrounding the first membrane region, wherein the outer grommet regioncomprises material of the first and second substrates that has beentransferred from the first membrane region.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic side view of a bonding apparatus.

FIG. 2 is a detailed view of the bonding apparatus of FIG. 1.

FIG. 3 is a perspective view a pattern roll.

FIG. 4 is a detailed isometric view of three pattern elements.

FIG. 5 is a top side view of the pattern elements of FIG. 4.

FIG. 6 is a cross-sectional view of a pattern element of FIG. 5 takenalong line 6-6.

FIG. 7 is a cross-sectional view of a pattern element of FIG. 5 takenalong line 7-7.

FIG. 8 is a detailed side view along the cross direction CD of the firstand second pattern elements of FIG. 5 bonding a first substrate with asecond substrate.

FIG. 9 is a detailed side view along the cross direction CD of the firstand third pattern elements of FIG. 5 bonding a first substrate with asecond substrate.

FIG. 10 is a detailed side view along the machine direction MD of thesecond and third pattern elements of FIG. 5 bonding a first substratewith a second substrate.

FIG. 11 is a top side view of a perspective view of a discrete bondregion.

FIG. 12 is a cross-sectional view of the bond region of FIG. 11 takenalong line 12-12.

FIG. 13 is a cross-sectional view of the bond region of FIG. 11 takenalong line 13-13.

FIG. 14 is a cross-sectional view of the bond region of FIG. 11 takenalong line 14-14.

FIG. 15 is a perspective view of a diaper pant.

FIG. 16A is a partially cut away plan view of the diaper pant shown inFIG. 15.

FIG. 16B is a partially cut away plan view of a second embodiment of adiaper pant.

FIG. 17A is a cross-sectional view of the diaper pants of FIGS. 16A and16B taken along line 17A-17A.

FIG. 17B is a cross-sectional view of the diaper pants of FIGS. 16A and16B taken along line 17B-17B.

FIG. 18 is a schematic side view of a converting apparatus adapted tomanufacture pre-fastened, pant diapers.

FIG. 19A is a view of a continuous length of chassis assemblies fromFIG. 18 taken along line A-A.

FIG. 19B1 is a view of a discrete chassis from FIG. 18 taken along lineB1-B1.

FIG. 19B2 is a view of a discrete chassis from FIG. 18 taken along lineB2-B2.

FIG. 19C is a view of continuous lengths of advancing front and backside panel material from FIG. 18 taken along line C-C.

FIG. 19D is a view of multiple discrete chassis spaced from each otheralong the machine direction MD and connected with each other by thefront and back side panel material from FIG. 18 taken along line D-D.

FIGS. 19E is a view of folded multiple discrete chassis with the frontand back side panel material in a facing relationship from FIGS. 18taken along line E-E.

FIGS. 19F is a view of two discrete absorbent articles advancing themachine direction MD from FIGS. 18 taken along line F-F.

FIG. 20 is a graphical representation illustrating strengths of discretebonds created by relatively small pattern element groupings andrelatively large pattern element groupings over a range of patternsurface pressures.

FIG. 21A illustrates the pattern element orientation of the InventiveNubs on a pattern roll in the machine direction MD and cross directionCD.

FIG. 21B illustrates the pattern element orientation of the Control Nubson a pattern roll in the machine direction MD and cross direction CD.

FIG. 22 illustrates an example test sample for use with the peelstrength test method.

DETAILED DESCRIPTION OF THE INVENTION

The following term explanations may be useful in understanding thepresent disclosure: “Absorbent article” is used herein to refer toconsumer products whose primary function is to absorb and retain soilsand wastes. “Diaper” is used herein to refer to an absorbent articlegenerally worn by infants and incontinent persons about the lower torso.The term “disposable” is used herein to describe absorbent articleswhich generally are not intended to be laundered or otherwise restoredor reused as an absorbent article (e.g., they are intended to bediscarded after a single use and may also be configured to be recycled,composted or otherwise disposed of in an environmentally compatiblemanner).

An “elastic,” “elastomer” or “elastomeric” refers to materialsexhibiting elastic properties, which include any material that uponapplication of a force to its relaxed, initial length can stretch orelongate to an elongated length more than 10% greater than its initiallength and will substantially recover back to about its initial lengthupon release of the applied force.

As used herein, the term “joined” encompasses configurations whereby anelement is directly secured to another element by affixing the elementdirectly to the other element, and configurations whereby an element isindirectly secured to another element by affixing the element tointermediate member(s) which in turn are affixed to the other element.

“Longitudinal” means a direction running substantially perpendicularfrom a waist edge to a longitudinally opposing waist edge of anabsorbent article when the article is in a flat out, uncontracted state,or from a waist edge to the bottom of the crotch, i.e. the fold line, ina bi-folded article. Directions within 45 degrees of the longitudinaldirection are considered to be “longitudinal.” “Lateral” refers to adirection running from a longitudinally extending side edge to alaterally opposing longitudinally extending side edge of an article andgenerally at a right angle to the longitudinal direction. Directionswithin 45 degrees of the lateral direction are considered to be“lateral.”

The term “substrate” is used herein to describe a material which isprimarily two-dimensional (i.e. in an XY plane) and whose thickness (ina Z direction) is relatively small (i.e. 1/10 or less) in comparison toits length (in an X direction) and width (in a Y direction).

Non-limiting examples of substrates include a web, layer or layers orfibrous materials, nonwovens, films and foils such as polymeric films ormetallic foils. These materials may be used alone or may comprise two ormore layers laminated together. As such, a web is a substrate.

The term “nonwoven” refers herein to a material made from continuous(long) filaments (fibers) and/or discontinuous (short) filaments(fibers) by processes such as spunbonding, meltblowing, carding, and thelike. Nonwovens do not have a woven or knitted filament pattern.

The term “machine direction” (MD) is used herein to refer to thedirection of material flow through a process. In addition, relativeplacement and movement of material can be described as flowing in themachine direction through a process from upstream in the process todownstream in the process.

The term “cross direction” (CD) is used herein to refer to a directionthat is generally perpendicular to the machine direction.

The term “yield” is used herein to refer to permanent and non-reversiblematerial displacement due to subjecting the material to mechanicalstress past the yield stress of the material and/or permanent andnon-reversible material displacement due to subjecting the material totemperatures higher than the melting point of the material.

The term “pant” (also referred to as “training pant”, “pre-closeddiaper”, “diaper pant”, “pant diaper”, and “pull-on diaper”) refersherein to disposable absorbent articles having a continuous perimeterwaist opening and continuous perimeter leg openings designed for infantor adult wearers. A pant can be configured with a continuous or closedwaist opening and at least one continuous, closed, leg opening prior tothe article being applied to the wearer.

The present disclosure relates to methods and apparatuses formanufacturing absorbent articles, and in particular, to methods andapparatuses for mechanically bonding substrates together. Theapparatuses may include a pattern roll and an anvil roll. The patternroll may include three or more pattern elements protruding radiallyoutward, wherein each pattern element includes a pattern surface. Andthe pattern roll may be adjacent the anvil roll to define a nip betweenthe pattern surfaces and the anvil roll, wherein the pattern roll isbiased toward the anvil roll to define a nip pressure between patternsurfaces and the anvil roll. As the first and second substrates advancebetween the pattern roll and anvil roll, the first substrate and thesecond substrate are compressed between the anvil roll and the patternsurfaces to form a discrete bond region between the first and secondsubstrates. More particularly, during the bonding process, heatgenerated by the nip pressure causes the first and second substratematerial to yield. And the yielded material is pressed together to forma bond region. In addition, some of the yielded material flows outwardfrom under the pattern surfaces to form one or more outer grommetregions along the outer perimeter of one or more pattern elements. Asdiscussed in more detail below, the pattern surfaces are also separatedfrom each other by gaps having minimum widths. As such, during thebonding process, some of the yielded material also flows from under thepattern surfaces and into the gaps to form gap grommet regions.

It is to be appreciated that various arrangements and configurations ofthe apparatuses and methods herein may be used to bond various types ofsubstrates together. For example, as discussed in more detail below,apparatuses and methods according to the present disclosure may beutilized to bond various substrates together during the production ofvarious components of absorbent articles, such as diapers.

FIG. 1 shows an embodiment of a bonding apparatus 100 that may be usedto bond a first substrate 102 and a second substrate 104 together toform a laminate 105. As shown in FIG. 1, the bonding apparatus 100 mayinclude a bonding roll 106, also referred to herein as a pattern roll106, adapted to rotate around an axis of rotation 108, and an anvil roll110 adapted to rotate around an axis of rotation 112. The anvil roll 110includes an outer circumferential surface 114. And as shown in FIGS.1-4, the pattern roll 106 may include one or more groupings 115 ofpattern elements 116, each pattern element 116 including a patternsurface 118. With particular reference to FIG. 4, the pattern roll 106may include a base circumferential surface 120, wherein each patternelement 116 includes a circumferential wall 122 that protrudes radiallyoutward from the base circumferential surface 120 to define a distance,Hp, between the pattern surface 118 and the base surface 120. Thecircumferential wall 122 also defines an outer perimeter 124 of thepattern element 116. It is to be appreciated that in some embodiments,the circumferential wall 122 may be perpendicular to basecircumferential surface 120 or may sloped or tapered with respect to thebase circumferential surface 120. As shown in FIGS. 1 and 2, the patternroll 106 is adjacent the anvil roll 110 so as to define a nip 126between the pattern roll 106 and the anvil roll 110, and moreparticularly, to define a nip 126 between the pattern surface 118 ofeach pattern element 116 and the anvil roll 110. As discussed in moredetail below, the pattern roll 106 may be biased toward the anvil roll110 to define a nip pressure between the pattern surface 118 and theanvil roll 106. It is to be appreciated that the anvil roll 110 may alsobe biased toward the pattern roll 106, and/or the pattern and anvilrolls may be biased toward each other to define the nip pressure betweenthe pattern surface 118 and the anvil roll 110. It is to be appreciatedthat the pattern roll 106 and the anvil roll 110 may be configured torotate such that the pattern surfaces 118 on the pattern roll 106 andthe outer circumferential surface 114 of the anvil roll 110 move at thesame speeds or different speeds. It is to be appreciated that thebonding methods and apparatuses herein can be configured to bondsubstrates together that are advancing at various speeds, such as forexample, speeds of about 240 feet or more per minute.

As shown in FIGS. 1 and 2, during the bonding operation, the patternroll 106 may rotate in a first direction 128 around the axis of rotation108 of the pattern roll 106, and the anvil roll 110 may rotate in asecond direction 130, opposite the first direction 128, around the axisof rotation 112 of the anvil roll 110. The first substrate 102 andsecond substrate 104 may advance in a machine direction MD between thepattern roll 106 and the anvil roll 110. More particularly, the firstsubstrate 102 includes a first surface 132 and a second surface 134opposite the first surface 132, and the second substrate 104 includes afirst surface 136 and a second surface 138 opposite the first surface136. As such, the first surface 132 of the first substrate 102 iscontacted by the pattern roll 106, and the second surface 138 of thesecond substrate 104 is contacted by the anvil roll 110. And the secondsurface 134 of the first substrate 102 and the first surface 136 of thesecond substrate 104 contact each other. As first substrate 102 andsecond substrate 104 advance through the nip 126 between the patternsurface 118 of a pattern element 116 and the anvil roll 110, the patternelement 116 contacts the first substrate 102 and compresses the firstsubstrate 102 and second substrate 104 between the pattern surface 118of the pattern element 116 and the anvil roll 110. In turn, heatgenerated by the nip pressure causes the first and second substratematerial to yield. And, as described below with reference to FIGS. 8-10,the pattern surface 118 presses yielded material 140 of the first andsecond substrates 102, 104 together to form a discrete bond region 142between the first and second substrates 102, 104. Thus, the apparatus100 may form a laminate 105 including first and second substrates 102,104 bonded together by discrete bond regions 142, without the use ofadhesives. It is to be appreciated, however, that the bonding apparatus100 may also be used in combination with adhesives. Although FIG. 1shows the apparatus 100 bonding two substrates together, it is to beappreciated that the apparatus may bond more than two substratestogether. In addition, it is to be appreciated that the apparatus mayalso be used to bond fibers of nonwoven together on a single substrateand/or emboss a pattern on a single substrate. It should also beappreciated that the pattern elements 116 may be configured with thesame or different distances, Hp, between the pattern surface 118 and thebase surface 120. In addition, the distance, Hp, may be greater than thesum of the thicknesses of the substrates 102, 104 being bonded.

It is to be appreciated that various pattern element configurations maybe used with the bonding apparatuses and processes herein. Variousquantities pattern elements may be arranged in groupings to formdiscrete bonds. For example, FIGS. 3-7 show a grouping 115 of patternelements 116 with pattern surfaces 118 separated by gaps 144. The gaps144 between the pattern elements provide a location, in addition toregions outside of and adjacent to the perimeter 124 of the patternelement 116, for yielded substrate material 140 to flow during thebonding process. Allowing yielded substrate material 140 to flow to thegaps 144 during the bonding process may help provide stress relief onthe pattern element 116, which may in turn, help reduce the frequency ofpattern element deformations, including buckling, and/or failures andmay help provide for more relatively more consistent and stronger bonds.

With continued reference back to FIGS. 4-7, the grouping 115 of patternelements 116 may include a first pattern element 116 a including a firstpattern surface 118 a; a second pattern element 116 b including a secondpattern surface 118 b; and a third pattern element 116 c including athird pattern surface 118 c. The first pattern element 116 a protrudesradially outward from the base circumferential surface 120 to define adistance, Hp1, between the first pattern surface 118 a and the basesurface 120. The second pattern element 116 b protrudes radially outwardfrom the base circumferential surface 120 to define a distance, Hp1,between the second pattern surface 118 b and the base surface 120. Thethird pattern element 116 c protrudes radially outward from the basecircumferential surface 120 to define a distance, Hp3, between the thirdpattern surface 118 c and the base surface 120. It is to be appreciatedthat the distances Hp1, Hp2, and/or Hp3 may be the same or different.Embodiments that are configured with distances Hp1, Hp2, and/or Hp3 aredifferent may utilize bearer ring configurations such as described inEuropean Patent Publication No. EP1635750B1.

Although the grouping 115 of pattern elements 116 is depicted asincluding three pattern elements, it is to be appreciated that groupingsmay include more than three pattern elements. As shown in FIG. 4, thefirst pattern surface 118 a and the second pattern surface 118 b areseparated by a first gap 144 a; the first pattern surface 118 a and thethird pattern surface 118 c are separated by a second gap 144 b; and thesecond pattern surface 118 b and the third pattern surface 118 c areseparated by a third gap 144 c. The first gap 144 a may define a minimumwidth, D1; the second gap 144 b may define a minimum width, D2; and thethird gap 144 c may define a minimum width, D3. As such, the firstpattern surface 118 a may be separated from the second and third patternsurfaces 118 b, 118 c by minimum distances of D1 and D2, respectively.And the second and third pattern surfaces may be separated from eachother by the minimum distance, D3. The pattern elements may be arrangedto also include gaps of various sizes. In some instances, the minimumwidths (D1, D2, D3) of the gaps 144 may be greater than 0.20 mm and lessthan about 3.00 mm. In some embodiments, the minimum widths D1, D2,and/or D3 of the gaps 144 may be about 0.30 mm. It is to be appreciatedthat in some pattern element groupings, the gap widths D1, D2, and/or D3may be the same or different.

It is to be appreciated that the apparatus 100 may also be configuredwith various different configurations of pattern elements 116. Forexample, the first pattern surface 118 a may define a first area, A1;the second pattern surface 118 b may define a second pattern area, A2;and the third pattern surface may define a third pattern area, A3. Assuch, the pattern elements may be configured to also include patternareas A of various sizes. In some instances, the pattern areas (A1, A2,A3) may be greater than about 0.25 mm² and less than about 2.00 mm²,. Insome embodiments, pattern areas A1, A2, and/or A3 may be about 0.70 mm².It is to be appreciated that in some pattern element groupings, thepattern areas A1, A2, and/or A3 may be the same or different. In otherexamples, the pattern roll may be configured with pattern elementshaving different sizes and shapes. For example, in some embodiments, thepattern elements may have a perimeter that defines circular, square,rectangular, and various types of other shapes. For example, the patternelements may have a perimeter that defines an elliptical shape, such asshown in FIG. 5. As such, in some embodiments, an elliptically shapedpattern element may have a major axis of about 1.27 mm and minor axis ofabout 0.56 mm. In some instances, the pattern elements may be configuredsuch that resulting bond regions also offer aesthetic benefits such as,for example, a stitched like appearance along with a relatively smoothtexture feel to the skin.

As discussed above, during the bonding process, the first and secondsubstrates 102, 104 advance in the machine direction MD between therotating pattern roll 106 and the anvil roll 110. As the pattern roll106 and the anvil rotate 110, the pattern surfaces 118 of the patternelements 116 contact the first substrate 106 and compress the first andsecond substrates 102, 104 in the nip 126 between the pattern surface118 and the outer circumferential surface 114 of the anvil roll 112. Nippressure between the pattern surface 118 of the pattern element 116 andthe anvil roll 110 exerted on the first and second substrates 102, 104causes some material 140 of the first and second substrates 102, 104 toyield. As shown in FIGS. 8-10, some of the yielded material 140 betweenthe pattern surfaces 118 a, 118 b, 118 c and the anvil roll 110 is fusedtogether in first locations 158 between the pattern surfaces 118 a, 118b, 118 c and the anvil roll 110. In addition, some of the yieldedmaterial 140 flows out from between the pattern surfaces 118 a, 118 b,118 c and the anvil roll 110 to second locations 160 along the perimeter124 of the pattern element 116. And some of the yielded material 140flows out from between the pattern surfaces 118 a, 118 b, 118 c and theanvil roll 110 to third locations 162 along the gaps 144 a, 144 b, 144c. As discussed in more detail below, the yielded material 140 in thefirst locations 158, second locations 160, and third locations 162 fusestogether to form a discrete bond 142 between the first substrate 102 andthe second substrate 104. More particularly, the yielded material 140 inthe first locations 158 fuses together to form membrane regions 164 ofthe bond 142; the yielded material 140 in the first locations 160 fusestogether to form outer grommet regions 166 of the bond 142; and theyielded material 140 in the third locations 162 fuses together to formgap grommet regions 168 of the bond 142.

FIGS. 11-14 show an example bond 142 between the first and secondsubstrates 102, 104 that may be created by the apparatus 100. As shownin FIG. 11, the bond 142 includes first regions 164, also referred to asmembrane regions 164, that correspond with the first locations 158wherein some of the yielded material 140 between the pattern surfaces118 and the anvil roll 110 is fused together between the patternsurfaces 118 and the anvil roll 110. In particular, the bond 142 mayinclude three membrane regions 164 a, 164 b, 164 c that correspond withthe pattern surfaces 118 a, 118 b, 118 c, respectively. The bond 142also includes second regions 166, also referred to as outer grommetregions 166, that correspond with the second locations 160 where some ofthe yielded material 140 that flowed out from between the patternsurfaces 118 and the anvil roll 110 to areas along the perimeter 124 ofthe pattern element 116 is fused together. In addition, the bond 142includes third regions 168, also referred to as gap grommet regions 168,that correspond with the third locations 162 where some of the yieldedmaterial 140 that flowed out from between the pattern surfaces 118 andthe anvil roll 110 to areas along the gaps 144 of the pattern element116 is fused together. In some embodiments, the bond 142 may includethree gap grommet regions 168 a, 168 b, 168 c that correspond with thefirst, second, and third gaps 144 a, 144 b, 144 c, respectively. Assuch, the outer region 166 may define a perimeter of the discrete bond142, the perimeter surrounding a central region of the discrete bond 142wherein the membrane regions 164 and the gap grommet regions 168 arelocated inside the central region.

As previously mentioned, the gaps 144 separating the pattern elementprovide locations, in addition to regions outside of and adjacent to theperimeters 124 of the pattern elements 116, for yielded substratematerial 140 to flow and form gap and outer grommet regions during thebonding process. In contrast, when bonding substrates with patternelements having relatively large pattern areas, yielded substratematerial may be required to flow relatively longer distances to formperimeter grommet regions outside of and adjacent the perimeter of thepattern element. Stated another way, when bonding substrates withpattern elements having relatively small pattern areas, yieldedsubstrate material may be required to flow relatively shorter distancesto form gap grommet and outer grommet regions. The relatively shorterflow distances of yielded material may also help reduce hydraulic-likereactionary pressures in the nip. Further, some air may be entrained insubstrates during formation, and collapse of the air bubbles, known ascavitation, may be significantly reduced by shortening the flow distancepath needed for grommet formation.

It is also to be appreciated that the grouping 115 of pattern elements116, such as shown in FIGS. 4-7, may create discrete bonds 142 havingsubstantially the same bond strengths as discrete bonds created bypattern elements of a larger size and separated by large gaps withreduced nip pressures. For example, FIG. 20 provides a graphillustrating strengths of discrete bonds created by relatively smallpattern element grouping and relatively large pattern element groupingsover a range of nip pressures between the pattern surfaces and the anvilroll. In generating the data represented in FIG. 20, a 15 gsmpolypropylene nonwoven substrate was bonded to a 12 gsm polypropylenenonwoven substrate with oval shaped, relatively small, pattern elementgroupings (Inventive Nubs 116). In addition, a 15 gsm polypropylenenonwoven substrate was bonded to a 12 gsm polypropylene nonwovensubstrate with oval shaped, relatively large, pattern element groupings(Control Nubs 117). FIG. 21A illustrates the pattern element orientationof the Inventive Nubs on a pattern roll in the machine direction MD andcross direction CD. And FIG. 21B illustrates the pattern elementorientation of the Control Nubs on a pattern roll in the machinedirection MD and cross direction CD.

TABLE 1 MD CD Distance Distance Pattern between Between Element MajorMinor Pattern Pattern Grouping Axis Axis Surfaces Surfaces Inventive1.27 mm 0.56 mm 0.31 mm 0.31 mm Nubs Control 2.18 mm 1.40 mm 3.54 mm1.82 mm Nubs

Table 1 above provides additional dimensional information about theoval-shaped Inventive Nub Grouping and the Control Nub Grouping used togenerate the data illustrated in FIG. 20. The nonwoven substrates werebonded to each other with the Inventive Nubs and Control Nubs at variousnip pressures between pattern surface and the anvil roll. The AveragePeak Bond Strengths of the bonds generated at the various nip pressureswere then measured according to the Peel Strength Test Method herein.

It is to be appreciated that bonds 142 formed with the methods andapparatuses herein may have regions of varying thicknesses or calipers.As shown in FIGS. 12-14, the discrete bond 142 includes a first surface170 opposite a second surface 172. A such, the bond may have: a firstthickness, C₁; between the first surface 170 and the second surface 172in the membrane regions 164; a second thickness, C₂; between the firstsurface 170 and the second surface 172 in the outer grommet region 166;and a third thickness, C₃; between the first surface 170 and the secondsurface 172 in the gap grommet region 168. In some embodiments, thesecond thickness, C₂, and the third thickness, C₃, may both be greaterthan the first thickness, C₁, and in some embodiments, the secondthickness, C₂, may also be greater than the third thickness, C₃. Inother embodiments, the second thickness, C₂, may be the same as or lessthan the third thickness, C₃. It is also to be appreciated that bonds142 formed with the methods and apparatuses herein may have varyingregions of different basis weights. For example, with continuedreference to

FIGS. 12-14, the membrane region 164 may have a first basis weight, BW₁;the outer grommet region 166 may have a second basis weight, BW₂; andthe gap grommet region 168 may have a third basis weight, BW₃. In someembodiments, the second basis weight, BW₂, and the third basis weight,BW₃, may both be greater than the first basis weight, BW₁., and in someembodiments, the second basis weight, BW₂, may also be greater than thethird basis weight, BW₃. In other embodiments, the second basis weight,BW₂, may be the same as or less than the third basis weight, BW₃.

It is also to be appreciated that bonds 142 formed with the methods andapparatuses herein may have varying regions of different opacities. Forexample, the membrane regions 164 may define a first opacity; the outergrommet region 166 may define a second opacity; and the gap grommetregion 168 may define a third opacity. In some embodiments, the secondand third opacities are greater than the first opacity.

It is to be appreciated that bonds having various differentcharacteristics may be formed with the apparatuses and methods herein.For example, in some embodiments wherein the bond 142 is formed bycompressing two substrates between the pattern surface 118 and arelatively smooth outer circumferential surface 114 of an anvil 110, thefirst, second, and third regions of the bond may protrude from therespective surfaces 170, 172 by different distances. For example, asshown in FIG. 14, the outer grommet region 166 defines a first maximumprotrusion height, PH_(1A), with respect to the first surface 170 anddefines a second maximum protrusion height, PH_(2A), with respect to thesecond surface 172. In some embodiments, the first maximum protrusionheight, PH_(1A), is greater than the second maximum protrusion height,PH_(2A). In addition, the bond may be configured such that the gapgrommet region 168 defines a first maximum protrusion height, PH_(1B),with respect to the first surface 170 and defines a second maximumprotrusion height, PH_(2B), with respect to the second surface 172. Insome embodiments, the first maximum protrusion height, PH_(1B), isgreater than the second maximum protrusion height, PH_(2B). When usingthe bonding apparatuses and methods herein to make absorbent articles,such as diapers for example, the bonds may be positioned on the articlesuch that the bond surfaces having relatively higher protrusion heightsface away from the wearer of the article.

It is to be appreciated that the bonding apparatus 100 may also beconfigured in various different ways. For example, different types ofmotor arrangements may be used to rotate the pattern roll 106 and anvilroll 110. For example, the pattern roll 106 and the anvil roll 110 maybe driven independently with two independent motors. In addition, thenip pressure between pattern surface and the anvil roll may be generatedin various ways. For example, as previously mentioned, the pattern rollmay be biased toward anvil roll; the anvil roll may be biased toward thepattern roll; or the pattern and anvil rolls may be biased toward eachother. The biasing of the rolls may be accomplished in various ways,such as described for example in U.S. Pat. No. 4,854,984. In someembodiments, the bonding apparatus 100 is configured to define a nippressure above 60,000 PSI between the pattern surface 118 and the anvilroll 110. In some embodiments, the bonding apparatus 100 is configuredto define a nip pressure from about 40,000 PSI to about 60,000 PSIbetween the pattern surface 118 and the anvil roll 110. In someembodiments, the bonding apparatus 100 is configured to define a nippressure of about 40,000 PSI between the pattern surface 118 and theanvil roll 110. In some embodiments, the bonding apparatus 100 isconfigured to define a nip pressure of about 50,000 PSI between thepattern surface 118 and the anvil roll 110. In some embodiments, thebonding apparatus 100 is configured to define a nip pressure of about60,000 PSI between the pattern surface 118 and the anvil roll 110. It isalso to be appreciated that the pattern roll and/or the anvil roll maybe heated.

It is to be appreciated that the apparatuses and methods herein can beused to bond various types of substrates together. For example, in someembodiments the apparatus may used to bond nonwoven substrates, such asfor example, polypropylene nonwoven, polyethylene film, bi-componentnonwoven or film, polyethylene terephthalate nonwoven or film. In someembodiments, the apparatuses and methods herein may be used to bond asubstrate which includes a mixture of cellulosic fibers and polyethyleneor polyethylene-polypropylene bicomponent fibers or particulate. In someembodiments, the substrates may have a basis weight of about 6 gsm toabout 100 gsm. Other types of substrates can be sandwiched in betweentwo layers of nonwovens or films.

As previously mentioned, the bonding apparatuses and methods herein mayused to bond various types of components used in the manufacture ofdifferent types of absorbent articles. To help provide additionalcontext to the previous discussion of the process and apparatusembodiments, the following provides a general description of absorbentarticles in the form of diapers that include components may be bondedwith the methods and apparatuses disclosed herein.

For the purposes of a specific illustration, FIGS. 15 and 16A show anexample of a diaper pant 300 that may be assembled in accordance withthe apparatuses and methods disclosed herein. In particular, FIG. 15shows a perspective view of a diaper pant 300 in a pre-fastenedconfiguration, and FIG. 16A shows a plan view of the diaper pant 300with the portion of the diaper that faces away from a wearer orientedtoward the viewer. The diaper pant 300 shown in FIGS. 15 and 16Aincludes a chassis 302 and a ring-like elastic belt 304. As discussedbelow in more detail, a first elastic belt 306 and a second elastic belt308 are connected together to form the ring-like elastic belt 304.

With continued reference to FIG. 16A, the chassis 302 includes a firstwaist region 316, a second waist region 318, and a crotch region 320disposed intermediate the first and second waist regions. The firstwaist region 316 may be configured as a front waist region, and thesecond waist region 318 may be configured as back waist region. In someembodiments, the length of each of the front waist region, back waistregion, and crotch region may be ⅓ of the length of the absorbentarticle 300. The diaper 300 may also include a laterally extending frontwaist edge 321 in the front waist region 316 and a longitudinallyopposing and laterally extending back waist edge 322 in the back waistregion 318. To provide a frame of reference for the present discussion,the diaper 300 and chassis 302 of FIG. 16A are shown with a longitudinalaxis 324 and a lateral axis 326. In some embodiments, the longitudinalaxis 324 may extend through the front waist edge 321 and through theback waist edge 322. And the lateral axis 326 may extend through a firstlongitudinal or right side edge 328 and through a midpoint of a secondlongitudinal or left side edge 330 of the chassis 302.

As shown in FIGS. 15 and 16A, the diaper pant 300 may include an inner,body facing surface 332, and an outer, garment facing surface 334. Thechassis 302 may include a backsheet 336 and a topsheet 338. The chassis302 may also include an absorbent assembly 340, including an absorbentcore 342, disposed between a portion of the topsheet 338 and thebacksheet 336. As discussed in more detail below, the diaper 300 mayalso include other features, such as leg elastics and/or leg cuffs toenhance the fit around the legs of the wearer.

As shown in FIG. 16A, the periphery of the chassis 302 may be defined bythe first longitudinal side edge 328, a second longitudinal side edge330, a first laterally extending end edge 344 disposed in the firstwaist region 316, and a second laterally extending end edge 346 disposedin the second waist region 318. Both side edges 328 and 330 extendlongitudinally between the first end edge 344 and the second end edge346. As shown in FIG. 16A, the laterally extending end edges 344 and 346are located longitudinally inward from the laterally extending frontwaist edge 321 in the front waist region 316 and the laterally extendingback waist edge 322 in the back waist region 318. When the diaper pant300 is worn on the lower torso of a wearer, the front waist edge 321 andthe back waist edge 322 of the chassis 302 may encircle a portion of thewaist of the wearer. At the same time, the chassis side edges 328 and330 may encircle at least a portion of the legs of the wearer. And thecrotch region 320 may be generally positioned between the legs of thewearer with the absorbent core 342 extending from the front waist region316 through the crotch region 320 to the back waist region 318.

It is to also be appreciated that a portion or the whole of the diaper300 may also be made laterally extensible. The additional extensibilitymay help allow the diaper 300 to conform to the body of a wearer duringmovement by the wearer. The additional extensibility may also help, forexample, the user of the diaper 300, including a chassis 302 having aparticular size before extension, to extend the front waist region 316,the back waist region 318, or both waist regions of the diaper 300and/or chassis 302 to provide additional body coverage for wearers ofdiffering size, i.e., to tailor the diaper to an individual wearer. Suchextension of the waist region or regions may give the absorbent articlea generally hourglass shape, so long as the crotch region is extended toa relatively lesser degree than the waist region or regions, and mayimpart a tailored appearance to the article when it is worn.

As previously mentioned, the diaper pant 300 may include a backsheet336. The backsheet 336 may also define the outer surface 334 of thechassis 302. The backsheet 336 may be impervious to fluids (e.g.,menses, urine, and/or runny feces) and may be manufactured from a thinplastic film, although other flexible liquid impervious materials mayalso be used. The backsheet 336 may prevent the exudates absorbed andcontained in the absorbent core from wetting articles which contact thediaper 300, such as bedsheets, pajamas and undergarments. The backsheet336 may also comprise a woven or nonwoven material, polymeric films suchas thermoplastic films of polyethylene or polypropylene, and/or amulti-layer or composite materials comprising a film and a nonwovenmaterial (e.g., having an inner film layer and an outer nonwoven layer).The backsheet may also comprise an elastomeric film. An examplebacksheet 336 may be a polyethylene film having a thickness of fromabout 0.012 mm (0.5 mils) to about 0.051 mm (2.0 mils). Exemplarypolyethylene films are manufactured by Clopay Corporation of Cincinnati,Ohio, under the designation BR-120 and BR-121 and by Tredegar FilmProducts of Terre Haute, Ind., under the designation XP-39385. Thebacksheet 336 may also be embossed and/or matte-finished to provide amore clothlike appearance. Further, the backsheet 336 may permit vaporsto escape from the absorbent core (i.e., the backsheet is breathable)while still preventing exudates from passing through the backsheet 336.The size of the backsheet 336 may be dictated by the size of theabsorbent core 342 and/or particular configuration or size of the diaper300.

Also described above, the diaper pant 300 may include a topsheet 338.The topsheet 338 may also define all or part of the inner surface 332 ofthe chassis 302. The topsheet 338 may be compliant, soft feeling, andnon-irritating to the wearer's skin. It may be elastically stretchablein one or two directions. Further, the topsheet 338 may be liquidpervious, permitting liquids (e.g., menses, urine, and/or runny feces)to penetrate through its thickness. A topsheet 338 may be manufacturedfrom a wide range of materials such as woven and nonwoven materials;apertured or hydroformed thermoplastic films; apertured nonwovens,porous foams; reticulated foams; reticulated thermoplastic films; andthermoplastic scrims. Woven and nonwoven materials may comprise naturalfibers such as wood or cotton fibers; synthetic fibers such aspolyester, polypropylene, or polyethylene fibers; or combinationsthereof. If the topsheet 338 includes fibers, the fibers may bespunbond, carded, wet-laid, meltblown, hydroentangled, or otherwiseprocessed as is known in the art.

Topsheets 338 may be selected from high loft nonwoven topsheets,apertured film topsheets and apertured nonwoven topsheets. Aperturedfilm topsheets may be pervious to bodily exudates, yet substantiallynon-absorbent, and have a reduced tendency to allow fluids to pass backthrough and rewet the wearer's skin. Exemplary apertured films mayinclude those described in U.S. Pat. Nos. 5,628,097; 5,916,661;6,545,197; and U.S. Pat. No. 6,107,539.

As mentioned above, the diaper pant 300 may also include an absorbentassembly 340 that is joined to the chassis 302. As shown in FIG. 16A,the absorbent assembly 340 may have a laterally extending front edge 348in the front waist region 316 and may have a longitudinally opposing andlaterally extending back edge 350 in the back waist region 318. Theabsorbent assembly may have a longitudinally extending right side edge352 and may have a laterally opposing and longitudinally extending leftside edge 354, both absorbent assembly side edges 352 and 354 may extendlongitudinally between the front edge 348 and the back edge 350. Theabsorbent assembly 340 may additionally include one or more absorbentcores 342 or absorbent core layers. The absorbent core 342 may be atleast partially disposed between the topsheet 338 and the backsheet 336and may be formed in various sizes and shapes that are compatible withthe diaper. Exemplary absorbent structures for use as the absorbent coreof the present disclosure are described in U.S. Pat. Nos. 4,610,678;4,673,402; 4,888,231; and U.S. Pat. No. 4,834,735.

Some absorbent core embodiments may comprise fluid storage cores thatcontain reduced amounts of cellulosic airfelt material. For instance,such cores may comprise less than about 40%, 30%, 20%, 10%, 5%, or even1% of cellulosic airfelt material. Such a core may comprises primarilyabsorbent gelling material in amounts of at least about 60%, 70%, 80%,85%, 90%, 95%, or even about 100%, where the remainder of the corecomprises a microfiber glue (if applicable). Such cores, microfiberglues, and absorbent gelling materials are described in U.S. Pat. Nos.5,599,335; 5,562,646; 5,669,894; and U.S. Pat. No. 6,790,798 as well asU.S. Patent Publication Nos. 2004/0158212 and 2004/0097895.

As previously mentioned, the diaper 300 may also include elasticized legcuffs 356. It is to be appreciated that the leg cuffs 356 can be and aresometimes also referred to as leg bands, side flaps, barrier cuffs,elastic cuffs or gasketing cuffs. The elasticized leg cuffs 356 may beconfigured in various ways to help reduce the leakage of body exudatesin the leg regions. Example leg cuffs 356 may include those described inU.S. Pat. Nos. 3,860,003; 4,909,803; 4,695,278; 4,795,454; 4,704,115;4,909,803; and U.S. Patent Publication No. 2009/0312730A1; and U.S.patent application Ser. No. 13/435,503, entitled “METHODS ANDAPPARATUSES FOR MAKING LEG CUFFS FOR ABSORBENT ARTICLES”, filed on Mar.30, 2012.

As mentioned above, diaper pants may be manufactured with a ring-likeelastic belt 304 and provided to consumers in a configuration whereinthe front waist region 316 and the back waist region 318 are connectedto each other as packaged, prior to being applied to the wearer. Assuch, diaper pants may have a continuous perimeter waist opening 310 andcontinuous perimeter leg openings 312 such as shown in FIG. 15.

As previously mentioned, the ring-like elastic belt 304 is defined by afirst elastic belt 306 connected with a second elastic belt 308. Asshown in FIG. 16A, the first elastic belt 306 defines first and secondopposing end regions 306 a, 306 b and a central region 306 c, and thesecond elastic 308 belt defines first and second opposing end regions308 a, 308 b and a central region 308 c.

The central region 306 c of the first elastic belt is connected with thefirst waist region 316 of the chassis 302, and the central region 308 cof the second elastic belt 308 is connected with the second waist region316 of the chassis 302. As shown in FIG. 15, the first end region 306 aof the first elastic belt 306 is connected with the first end region 308a of the second elastic belt 308 at first side seam 378, and the secondend region 306 b of the first elastic belt 306 is connected with thesecond end region 308 b of the second elastic belt 308 at second sideseam 380 to define the ring-like elastic belt 304 as well as the waistopening 310 and leg openings 312. As discussed in more detail below,bonding apparatuses 100 herein may be used to create discrete bondregions 142 that connect first and second elastic belts 306, 308together at the first and second side seams 378, 380.

As shown in FIGS. 16A, 17A, and 17B, the first elastic belt 306 alsodefines an outer lateral edge 307 a and an inner lateral edge 307 b, andthe second elastic belt 308 defines an outer lateral edge 309 a and aninner lateral edge 309 b. The outer lateral edges 307 a, 307 b may alsodefine the front waist edge 320 and the laterally extending back waistedge 322. The first elastic belt and the second elastic belt may alsoeach include an outer, garment facing layer 362 and an inner, wearerfacing layer 364. It is to be appreciated that the first elastic belt306 and the second elastic belt 308 may comprise the same materialsand/or may have the same structure. In some embodiments, the firstelastic belt 306 and the second elastic belt may comprise differentmaterials and/or may have different structures. It should also beappreciated that the first elastic belt 306 and the second elastic belt308 may be constructed from various materials. For example, the firstand second belts may be manufactured from materials such as plasticfilms; apertured plastic films; woven or nonwoven webs of naturalmaterials (e.g., wood or cotton fibers), synthetic fibers (e.g.,polyolefins, polyamides, polyester, polyethylene, or polypropylenefibers) or a combination of natural and/or synthetic fibers; or coatedwoven or nonwoven webs. In some embodiments, the first and secondelastic belts include a nonwoven web of synthetic fibers, and mayinclude a stretchable nonwoven. In other embodiments, the first andsecond elastic belts include an inner hydrophobic, non-stretchablenonwoven material and an outer hydrophobic, non-stretchable nonwovenmaterial.

The first and second elastic belts 306, 308 may also each include beltelastic material interposed between the outer layer 362 and the innerlayer 364. The belt elastic material may include one or more elasticelements such as strands, ribbons, or panels extending along the lengthsof the elastic belts. As shown in FIGS. 16A, 17A, and 17B, the beltelastic material may include a plurality of elastic strands 368 whichmay be referred to herein as outer, waist elastics 370 and inner, waistelastics 372. As shown in FIG. 16A, the elastic strands 368 continuouslyextend laterally between the first and second opposing end regions 306a, 306 b of the first elastic belt 306 and between the first and secondopposing end regions 308 a, 308 b of the second elastic belt 308. Insome embodiments, some elastic strands 368 may be configured withdiscontinuities in areas, such as for example, where the first andsecond elastic belts 306, 308 overlap the absorbent assembly 340. Insome embodiments, the elastic strands 368 may be disposed at a constantinterval in the longitudinal direction. In other embodiments, theelastic strands 368 may be disposed at different intervals in thelongitudinal direction. The belt elastic material in a stretchedcondition may be interposed and joined between the uncontracted outerlayer and the uncontracted inner layer. When the belt elastic materialis relaxed, the belt elastic material returns to an unstretchedcondition and contracts the outer layer and the inner layer. The beltelastic material may provide a desired variation of contraction force inthe area of the ring-like elastic belt.

It is to be appreciated that the chassis 302 and elastic belts 306, 308may be configured in different ways other than as depicted in FIG. 16A.For example, FIG. 16B shows a plan view of a diaper pant 300 having thesame components as described above with reference to FIG. 16A, exceptthe first laterally extending end edge 344 of the chassis 302 is alignedalong and coincides with the outer lateral edge 307 a of the firstelastic belt 306, and the second laterally extending end edge 346 isaligned along and coincides with the outer lateral edge 309 a of thesecond belt 308.

As previously mentioned, the apparatuses and methods according to thepresent disclosure may be utilized to assemble various components ofdiapers 300. For example, FIG. 18 shows a schematic view of a convertingapparatus 500 adapted to manufacture pant diapers 300. The method ofoperation of the converting apparatus 500 may be described withreference to the various components of pant diapers 300 described aboveand shown in FIGS. 15 and 16A. Although the following methods areprovided in the context of the diaper 300 shown in FIGS. 15 and 16A, itis to be appreciated that various embodiments of diaper pants can bemanufactured according to the methods disclosed herein, such as forexample, the absorbent articles disclosed in U.S. Pat. No. 7,569,039and; U.S. Patent Publication Nos. 2005/0107764A1, US2012/0061016A1, andUS2012/0061015A1, which are all hereby incorporated by reference herein.

As described in more detail below, the converting apparatus 500 shown inFIG. 18 operates to advance discrete chassis 302 along a machinedirection MD such that the lateral axis of each chassis 302 is parallelwith the machine direction, and wherein the chassis 302 are spaced apartfrom each other along the machine direction. Opposing waist regions 316,318 of the spaced apart chassis 302 are then connected with continuouslengths of advancing first and second elastic belt substrates 606, 608.The chassis 302 are then folded along the lateral axis to bring thefirst and second elastic belt substrates 606, 608 into a facingrelationship, and the first and second elastic belt substrates areconnected together along regions 536 intermittently spaced along themachine direction, wherein each region 536 may include one or morediscrete bond sites 142. And the elastic belt substrates 606, 608 arecut along the regions 536 to create discrete diapers 300, such as shownin FIG. 15. As shown in FIGS. 18 and 17A, a continuous length of chassisassemblies 502 are advanced in a machine direction MD to a carrierapparatus 508 and cut into discrete chassis 302 with knife roll 506. Thecontinuous length of chassis assemblies may include absorbent assemblies340 sandwiched between topsheet material 338 and backsheet material 336,leg elastics, barrier leg cuffs and the like. A portion of the chassisassembly is cut-away to show a portion of the topsheet material 338 andan absorbent assembly 340.

After the discrete absorbent chassis 302 are cut by the knife roll 506,the carrier apparatus 508 rotates and advances the discrete chassis 302in the machine direction MD in the orientation shown in FIG. 19B1,wherein the longitudinal axis 324 of the chassis 302 is generallyparallel with the machine direction MD. While the chassis 302 shown inFIG. 19B1 is shown with the second laterally extending end edge 346 as aleading edge and the first laterally extending end edge 344 as thetrailing edge, it is to be appreciated that in other embodiments, thechassis 302 may be advanced in other orientations. For example, thechassis may be oriented such that the second laterally extending endedge 346 is a trailing edge and the first laterally extending end edge344 is a leading edge. The carrier apparatus 508 also rotates while atthe same time changing the orientation of the advancing chassis 302. Thecarrier apparatus 508 may also change the speed at which the chassis 302advances in the machine direction MD. It is to be appreciated thatvarious forms of carrier apparatuses may be used with the methodsherein, such as for example, the carrier apparatuses disclosed in U.S.Pat. No. 7,587,966. FIG. 19B2 shows the orientation of the chassis 302on the carrier apparatus 508 while advancing in the machine direction.More particularly, FIG. 19B2 shows the chassis 302 with the lateral axis326 of the chassis 302 generally parallel with the machine direction MD,and wherein the second longitudinal side edge 330 is the leading edgeand the first longitudinal side edge 328 is the trailing edge.

As discussed below with reference to FIGS. 18, 19C, 19D, 19E, and 19F,the chassis 302 are transferred from the carrier apparatus 508 andcombined with advancing, continuous lengths of belt substrates 606, 608,which are subsequently cut to form first and second elastic belts 306,308 on diapers 300.

With reference to FIGS. 17 and 19C, the chassis 302 are transferred fromthe carrier apparatus 508 to a nip 516 between the carrier apparatus 508and a carrier apparatus 518 where the chassis 302 is combined withcontinuous lengths of advancing front belt 606 and back belt 608substrate material. The front belt substrate material 606 and the backbelt substrate material 608 each define a wearer facing surface 512 andan opposing garment facing surface 514. The wearer facing surface 512 ofthe first belt substrate 606 may be combined with the garment facingsurface 334 of the chassis 302 along the first waist region 316, and thewearer facing surface 512 of the second belt substrate 608 may becombined with the garment facing surface 334 of the chassis 302 alongthe second waist region 318. As shown in FIG. 18, adhesive 520 may beintermittently applied to the wearer facing surface 512 of the first andsecond belt substrates 606, 608 before combining with the discretechassis 302 at the nip 516 between roll 518 and the carrier apparatus508.

With reference to FIGS. 18 and 19D, a continuous length of absorbentarticles 600 are defined by multiple discrete chassis 302 spaced fromeach other along the machine direction MD and connected with each otherby the second belt substrate 608 and the first belt substrate 606. Asshown in FIG. 18, the continuous length of absorbent articles 600advances from the nip 516 to a folding apparatus 500. At the foldingapparatus 500, each chassis 302 is folded in the cross direction CDalong a lateral axis 326 to place the first waist region 316, andspecifically, the inner, body facing surface 332 into a facing, surfaceto surface orientation with the inner, body surface 332 of the secondwaist region 318. The folding of the chassis also positions the wearerfacing surface 512 of the second belt substrate 608 extending betweeneach chassis 302 in a facing relationship with the wearer facing surface512 of the first belt substrate 606 extending between each chassis 302.As shown in FIGS. 18, 19D, and 19E, the folded discrete chassis 302connected with the first and second belt substrates 606, 608 areadvanced from the folding apparatus 500 to a bonder apparatus 100, suchas described above. The bonder apparatus 100 operates to bond an overlaparea 362, thus creating discrete bond sites 142. The overlap area 362includes a portion of the second belt substrate 608 extending betweeneach chassis 302 and a portion of the first belt substrate 606 extendingbetween each chassis 302. As shown in FIGS. 18 and 19F, a continuouslength of absorbent articles are advanced from the bonder 100 to a kniferoll 538 where the regions 536 are cut into along the cross direction tocreate a first side seam 378 on an absorbent article 300 and a secondside seam 380 on a subsequently advancing absorbent article.

Although the absorbent article is described as having a first and secondbelt substrate, it is to be appreciated that the absorbent article mayhave only one belt substrate. Further, it is to be appreciated that thechassis and belt substrate of the absorbent article may be onecontinuous substrate such that the overlap area is formed from the samesubstrate. As such, the bonder apparatus may operate to bond acontinuous substrate at an overlap area to form one or more discretebond sites.

Although the apparatuses and methods have been described in the contextof the diapers 300 shown in FIGS. 15, 16A, and 16B, it is to beappreciated that the methods and apparatuses herein may be used toassemble and bond various substrates and/or elastic laminates that canbe used with various process configurations and/or absorbent articles,such as for example, disclosed in U.S. Pat.No. 7,569,039; U.S. PatentPublication Nos. US2005/0107764A1, US2012/0061016A1, andUS2012/0061015A1; U.S. patent application Ser. No. 13/434,984, filed onMar. 30, 2012; U.S. patent application Ser. No. 13/435,036, filed onMar. 30, 2012; U.S. patent application Ser. No. 13/435,063, filed onMar. 30, 2012; U.S. patent application Ser. No. 13/435,247, filed onMar. 30, 2012; and U.S. patent application Ser. No. 13/435,503, filed onMar. 30, 2012, all of which are incorporated by reference herein. Forexample, the bonding apparatuses and methods herein can be used to applytack-down bonds on leg cuffs, such as described in U.S. patentapplication Ser. No. 13/435,503, entitled “METHODS AND APPARATUSES FORMAKING LEG CUFFS FOR ABSORBENT ARTICLES”, filed on Mar. 30, 2012.

In the context of the previous discussion, the apparatuses 100 andmethods herein may be used to provide for the application of bonds 142in patterns to substrates and components during the manufacture of anabsorbent article. For example, bonds 142 may be applied in variouspatterns to portions of any of the topsheet, backsheet, absorbent core,leg cuffs, waist feature, ears, and fastening elements during themanufacture of an absorbent article. In some instances, the adhesive maybe used in combination with the bonding methods herein.

Peel Strength Test Method

Bond Strength is measured using a 180° T-peel test on a constant rate ofextension tensile tester with computer interface (a suitable instrumentis the MTS Model Q-Test/1 using Testworks 4.0 Software, as availablefrom MTS Systems Corp., Eden Prairie, Minn.) using a load cell for whichthe forces measured are within 10% to 90% of the limit of the cell. Boththe movable (upper) and stationary (lower) pneumatic jaws are fittedwith smooth stainless steel faced grips, 25.4 mm in height and widerthan the width of the test specimen. Air pressure supplied to the jawsis sufficient to prevent sample slippage. All testing is performed in aconditioned room maintained at about 23° C.±2 C.° and about 50° C.±2 C.°relative humidity.

Condition the samples at 23±2° C. and 50%±2% relative humidity for atleast 24 hours prior to testing. Identify the bond site to be tested.The test specimen consists of the bond and the two material layers whichare bonded together. Using a razor knife or scissors cut the specimen25.4 mm±0.1 mm in the dimension parallel to the bond, and preferably50.8 mm in the dimension perpendicular to and centered on the bond. If a50.8 mm perpendicular length cannot be harvested from the article,attach leads made from adhesive tape (e.g., duct tape) to the specimenfor use to secure it in the tensile tester's grip faces.

Program the tensile tester to perform an extension test, collectingforce and extension data at an acquisition rate of 50 Hz as thecrosshead raises at a rate of 304 mm/min until the two layers areseparated.

Set the gage length to 25.4 mm±0.1 mm and zero the crosshead position.Referring to FIG. 22, position the end of the first layer (or attachedleader) 702 within the upper grip faces. Align the specimen 700vertically with the bond site 703 centered between the upper and lowergrip faces and close the upper grip faces. With the specimen hangingdownward and not touching the bottom fixture, zero the load cell.Position the second layer (or attached leader) 704 within the lower gripfaces and close. The specimen should be under enough tension toeliminate any slack, but less than 0.05 N of force on the load cell.

Start the test and collect data. From the resulting Force (N) versusExtension (mm) curve, calculate the Maximum Peak Force (N). Calculatethe Bond Strength (N/m) as the Peak Force (N) divided by the specimenwidth (m) and record to the nearest 0.1 N/m.

Repeat the test on a total of ten substantially identical articlesselecting the corresponding test site on each article. Report theaverage Bond Strength (N/m) to the nearest 0.1 N/m.

End of Peel Strength Test Method

This application is a divisional of U.S. application Ser. No.14/301,416, filed on Jun. 11, 2014, which claims the benefit of U.S.Provisional Application No. 61/836,745, filed Jun. 19, 2013, theentireties of which are incorporated by reference herein.

The dimensions and values disclosed herein are not to be understood asbeing strictly limited to the exact numerical values recited. Instead,unless otherwise specified, each such dimension is intended to mean boththe recited value and a functionally equivalent range surrounding thatvalue. For example, a dimension disclosed as “40 mm” is intended to mean“about 40 mm.”

Every document cited herein, including any cross referenced or relatedpatent or application, is hereby incorporated herein by reference in itsentirety unless expressly excluded or otherwise limited. The citation ofany document is not an admission that it is prior art with respect toany invention disclosed or claimed herein or that it alone, or in anycombination with any other reference or references, teaches, suggests ordiscloses any such invention. Further, to the extent that any meaning ordefinition of a term in this document conflicts with any meaning ordefinition of the same term in a document incorporated by reference, themeaning or definition assigned to that term in this document shallgovern.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A method of bonding substrates, the methodcomprising the steps of: rotating an anvil roll; rotating a pattern rolladjacent the anvil roll, the pattern roll including a basecircumferential surface, a first pattern element including a firstpattern surface, a second pattern element including a second patternsurface, and a third pattern element including a third pattern surface;wherein each pattern surface defines an area, A, wherein A is greaterthan about 0.25 mm² and less than about 2.00 mm²; wherein each patternelement protrudes outward from the base circumferential surface todefine a distance, Hp, between the first, second, and third patternsurfaces and the base surface, and wherein each pattern element isbounded by a perimeter; wherein the first and second pattern surfacesare separated by a first gap having a minimum width, D1, wherein thefirst and third pattern surfaces are separated by a second gap having aminimum width, D2, and wherein the second and third pattern surfaces areseparated by a third gap having a minimum width, D3, and wherein D1, D2,and D3 are greater than 0.20 mm and less than about 3.00 mm; biasing thebonding roll toward the anvil roll to define a nip pressure of greaterthan about 40,000 PSI and less than about 60,000 PSI between eachpattern surface and the anvil roll; advancing a first substrate and asecond substrate in a machine direction between the pattern roll and theanvil roll; and compressing the first substrate and the second substratebetween the anvil roll and the first, second, and third pattern surfacesto form a discrete bond region between the first and second substrates.2. The method of claim 1, wherein the step of compressing furthercomprises moving a first portion of material of the first and secondsubstrates from between the first pattern surface and the anvil to thefirst gap and the second gap.
 3. The method of claim 2, wherein the stepof compressing further comprises moving a second portion of material ofthe first and second substrates from between the second pattern surfaceand the anvil to the first gap and the third gap.
 4. The method of claim3, wherein the step of compressing further comprises moving a thirdportion of material of the first and second substrates from between thethird pattern surface and the anvil to the second gap and the third gap.5. The method of claim 1, wherein each pattern surface definessubstantially the same area, A.
 6. The method of claim 5, wherein thearea, A, is about 0.70 mm².
 7. The method of claim 1, wherein at leastone of D1, D2, and D3 is about 0.30 mm.
 8. The method of claim 1,wherein D1, D2, and D3 are substantially the same.